Wheel bearings having rotational speed sensors are used extensively in automotive engineering, in particular in connection with anti-lock braking systems (ABS). For this purpose, signal transmitters in the form of encoders, in particular multipole encoders, are mounted on the wheel hub or an inner ring of the wheel hub for the purpose of executing the rotary rotation and being sensed by a detector.
Unfortunately, particles accumulate on the encoder, which are magnetizable thereby because they are attracted by its alternating magnetic north and south poles (ferromagnetic dirt particles). This results in a magnetic short-circuit at the poles or even damage, which threatens the functionality of the ABS system or even causes it to fail. In the past, encoders were protected with sheet metal rings or sheet metal caps to prevent this from happening.
A wheel bearing having a cover sheet is known from EP 0 968 851 B1, which is fastened to the outer ring of the wheel bearing and bridges the contact area to the joint bell housing, a static sealing lip being fastened axially on the end of the cover sheet and resting against the joint bell housing to form a seal.